Low-key love. Cole Sprouse praised his girlfriend, Lili Reinhart, on Valentine’s Day with a sweet message.

“Quite actually the only thing keeping me sane is @lilireinhart,” Sprouse, 26, captioned an Instagram snapshot of his Riverdale costar on Thursday, February 14. Reinhart, 22, also showered her beau with love via Instagram on Cupid’s special day, sharing a selfie of them alongside the caption, “You make me very happy. Happy Valentine’s Day, my love.”

The private pair, who star as lovebirds Betty Cooper and Judghead Jones on the hit CW series, sparked romance rumors in July 2017 after they were spotted locking lips at a Comic Con party in San Diego, California. Although they’ve been going strong ever since, they are committed to keeping their romance under wraps.

“It’s not something that we hide or it’s not something that we show off,” Sprouse explained to GQ in a profile published on Thursday about keeping his relationship on the down-low. “It’s just something that exists.”

Reinhart shared a similar sentiment with Harper’s Bazaar in July 2018. “I’m not OK talking about my relationship,” she explained at the time. “I’m not going to tell you my love story. That’s just not appropriate right now.”

The Miss Stevens actress also spoke to Seventeen magazine about her private romance with the Suite Life of Zack & Cody alum in April 2018, one month before the duo made their red carpet debut at the Met Gala in New York City.

“Every time someone asks me about it, I make a decision then and there whether I’m comfortable. It’s not like I’m in some kind of contract, but I’m not in a place where I want to talk about it and that’s totally fine,” she noted. “It’s called a private life for a reason — it’s mine and it’s special and sacred. My relationships are between me and whomever I’m with, not me and the world.”

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